Powered hand slips

ABSTRACT

Hand slips having an automated device for raising and lowering the hand slips including a mounting bracket, a motor and a yoke connected to the hand slips using a suitable linkage.

CROSS REFERENCES TO RELATED APPLICATIONS

None

STATEMENTS AS TO RIGHTS TO INVENTIONS MADE UNDER FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT

NONE

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an apparatus for automating the setting and releasing of hand slips on a drilling rig. More particularly, the present invention relates to an automated apparatus for actuating hand slips used during the installation of casing and/or other pipe in a well.

2. Brief Description of the Prior Art

Standard rotary drilling rigs are typically comprised of a supportive rig floor, a substantially vertical derrick extending above said rig floor, and a traveling block or other hoisting mechanism employing elevators that can be raised and lowered within said derrick. In most cases, such derrick is situated above a well bore to be drilled or serviced. During drilling or servicing operations, such rig equipment is often used to manipulate tubular goods, such as pipe, in and out of a well bore.

Drill bits and other equipment used in connection with the drilling, servicing and/or equipping of wells are typically conveyed into and out of such wells on tubular pipe known as “drill pipe” or “drill string.” Further, once a well has been drilled to a desired depth, large diameter pipe called casing is frequently installed in the well and cemented in place. Such casing is typically installed to provide structural integrity to the well bore and keep geologic formations isolated from one another.

Casing, drill pipe or other similar tubular goods are all typically introduced into a well in essentially the same manner. The pipe is generally inserted into a well in a number of different sections of roughly equal length. Single sections of pipe called “joints,” or groupings of joints commonly referred to as “stands,” are typically screwed together or otherwise joined end-to-end at the rig in order to form a substantially continuous “string” of pipe that reaches downward into the earth's surface. As the bottom or distal end of the pipe string penetrates further into a well, additional sections of pipe are added to the ever-lengthening pipe string at the rig. Conversely, when pipe is being removed from a well bore, the pipe string is pulled from the well and joints (or stands, as the case may be) are unscrewed in the rig derrick until all of the pipe has been retrieved from said well.

The specific process of inserting a string of pipe in a well is typically commenced by grasping a first section of pipe within elevators that are in turn attached to a traveling block or other hoisting mechanism operable within a rig derrick. Said first section of pipe is lowered into a well bore via such elevators, and thereafter suspended or hung in place at the rig floor. Once said section of pipe is secured in place at the rig floor, the elevators are unlatched from said section of pipe and the process is repeated with subsequent sections of pipe.

During the process of installing casing into a well, a device known as a casing spider is frequently used to support such casing. A casing spider typically rests on the rig floor over the well bore. The spider supports the casing string in the well bore by means of slips, which typically comprise a plurality of wedge-shaped elements that circumferentially surround the casing string to grip the exterior surface of such casing. Such slips can be received within a housing, commonly referred to as a “bowl,” which represents the surfaces on the inner bore of the spider.

The inner sides of the slips usually carry teeth formed of hard metal dies for engaging against the exterior surface of a section of pipe. The exterior surface of the slips, and the interior surface of the bowl, has opposing engaging surfaces that are inclined and downwardly converging. Such inclined surfaces allow the slips to move vertically and radially relative to the bowl. In effect, the inclined surfaces of the slips and bowl serve as a camming surface for engaging the slips against the exterior surface of a section of pipe. As such, when the weight of the casing string is transferred to the slips, the slips will move downwardly with respect to the bowl along the inclined surfaces. Such inclined surfaces urge the slips to move radially inward to engage the casing string. Further, the slips are designed to prohibit release of the casing string until the casing string load is supported by another means such as the elevator.

Although some spider slips are fully automated, in many cases “hand slips” are used in connection with casing spiders. Such hand slips are manually lowered into a spider bowl to engage against and grip a section of pipe. When the casing is to be supported by other means (such as via the elevators), the hand slips are manually removed from the spider bowl.

The process of manually manipulating hand slips can be inefficient, difficult and, in many cases, dangerous. When setting hand slips, personnel are typically required to grab such hand slips, lift the slips and insert them into a spider bowl around the exterior of a section of pipe. Alternatively, when removing hand slips, personnel are generally required to grab the slips and lift such slips out of a spider bowl. Because casing spiders are frequently situated at or near the rig floor, such actions often require personnel to bend over and/or lift in awkward positions, thereby increasing the risk of injury to such personnel.

Thus, there is a need for an automated means for raising hand slips from a spider bowl in order to disengage such slips from a section of pipe and, alternatively, lowering said slips into said slip bowl in order to engage such slips against a section of pipe. Said automated means should be easily integrated with existing rig equipment, and should facilitate easy and efficient handling of tubular goods on a drilling rig, such as casing, drill pipe and/or the like.

SUMMARY OF THE PRESENT INVENTION

The present invention generally comprises a mounting bracket that can be easily attached to a spider body having a central opening forming an inclined surface known as a spider bowl. In the preferred embodiment, said mounting bracket can be attached to a side of a spider body. However, it is to be observed that said mounting bracket could be beneficially attached to other parts of a spider body or device without departing from the scope of the present invention.

At least one collar having an inclined shoulder partially surrounds the opening to the spider bowl along the upper surface of said spider body. Said inclined shoulder is wider at the top than at the bottom, thereby defining a funnel-like collar that radially surrounds a portion of the opening to said spider bowl.

A lifting mechanism is attached to said mounting bracket and is offset from the upper opening of the spider bowl. Said lifting mechanism comprises a motor, a yoke having a slightly larger diameter than the opening of the mounting bracket, and at least one lever arm extending from said yoke to said motor. In the preferred embodiment, said motor is a rotary actuator having a horizontal drive shaft, wherein said drive shaft is oriented generally perpendicular to the central axis of the spider bowl.

Hand slips are aligned with said spider bowl, and are connected to said yoke using suitable linkages. Said slips are pivotally operable between an upper, retracted position and a lower, gripping position. The slips are moved between such upper and lower positions by the lifting mechanism of the present invention. Specifically, when actuated, the motor causes said at least one lever arm to pivot about a pivot axis passing through the drive shaft of the motor that, in turn, causes the yoke to move in the desired direction. Movement of the yoke results in movement of the slips in the desired direction. During normal raising or lowering of the slips, the motor acts to retain such slips in the upper or lower position. The rate of raising or lowering the slips can be controlled by said motor that, in turn, can be controlled from a remote location using a remote control device.

Existing spiders devices also typically have a locking mechanism to lock slips in an upper, retracted position. If the slips should fall to the lower gripping position while pipe is being raised or lowered through the spider bowl, the movement of the pipe would be impeded and damage could occur to the casing or other drilling equipment. Unlike mechanical locking mechanisms of the prior art, the present invention is not susceptible to the jarring and vibration, which commonly occurs during typical drilling operations.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts an exploded perspective view of the powered hand slips of the present invention.

FIG. 2 depicts a side view of the lifting mechanism of the powered hand slips of the present invention.

FIG. 3 depicts an overhead view of the lifting mechanism of the powered hand slips of the present invention.

FIG. 4 depicts a side view of the powered hand slips of the present invention installed on a spider body.

FIG. 5 depicts an overhead view of the powered hand slips of the present invention installed on a spider body.

FIG. 6 depicts a side view of the present invention in a raised position installed on a well.

FIG. 7 depicts a side view of the present invention, in a lowered position, installed on a well.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

Referring to the drawings, FIG. 1 depicts an exploded perspective view of powered hand slips 1 of the present invention. The present invention generally comprises a mounting bracket 10 that can be easily attached to a spider body 20 having a spider bowl 21. In the preferred embodiment, said mounting bracket 10 can be attached to the side of any number of existing spider bodies, such as spider body 20, with minimal modifications to said spider body. As such, the powered hand slips of the present invention do not require installation of a specialized master bushing, or removal of an existing master bushing, in order to install large diameter pipe (such as casing) into a well. Further, although mounting bracket 10 can attach to the side of spider body 20, it is to be observed that said mounting bracket 10 can alternatively be beneficially attached to other parts of an existing spider body without limiting or departing from the scope or function of the present invention.

Spider body 20 is one of many prior art spider devices that are currently well known to those having skill in the art. Said spider body 20 has a central bore extending through said spider body, including spider bowl 21. Spider body 20 is typically installed at or near the rig floor of a drilling rig. The interior surface of spider bowl 21 has an inclined and downwardly converging (that is, bowl-shaped) inner surface. Said inner surface of spider bowl 21 remains stationary, and cooperates with the inclined exterior surface of hand slips (not shown in FIG. 1), thereby allowing such slips to move vertically and radially relative to said spider bowl 21.

The cooperating inclined surfaces of spider bowl 21 and slips situated therein serve to engage said slips against the exterior surface of a section of pipe (not depicted in FIG. 1) extending through said spider bowl 21. As such, when the weight of such pipe (such as a casing string or the like) is transferred to the slips, such slips will move downwardly relative to stationary spider bowl 21. The cooperating inclined surfaces of the slips and spider bowl 21 urge said slips to move radially inward to engage against such pipe.

Collars 30 and 31 can be mounted to the upper surface of spider body 20 and surround the opening of spider bowl 21 along the upper surface of said spider body 20. Said collars 30 and 31 define inclined shoulders that are wider at the upper end of said collars (30 a and 31 a) than at the bottom of said collars (30 b and 31 b), thereby defining a funnel-like guide that surrounds the upper opening to spider bowl 21.

FIG. 2 depicts a side view of lifting mechanism 40 of the powered hand slips of the present invention. Said lifting mechanism 40 comprises motor 41 (partially obscured from view in FIG. 2), yoke 42 and at least one lever arm 43 extending from said motor 41 to said yoke 42. In the preferred embodiment, motor 41 is attached to mounting bracket 10 using mounting plate 44. However, it is to be observed that motor 41 can be affixed to mounting bracket 10 using any number of different methods.

FIG. 3 depicts an overhead view of lifting mechanism 40 of the powered hand slips of the present invention. Motor 41 is affixed to mounting plate 44. In the preferred embodiment, motor 41 is a rotary actuator having horizontal drive shaft 45. Lever arms 43 extend from drive shaft 45 of motor 41 to yoke 42. As such, yoke 42 is pivotally attached to motor 41 (via drive shaft 45). Motor 41 is controlled from a remote location using a remote controller for said motor 41. In this manner, an operator can be located in the vicinity of the wellbore, and can visually observe operation of the powered hand slips of the present invention; however, the operator can be situated far enough away to avoid obstructing pipe handling activities.

In the preferred embodiment, motor 41 can be powered using hydraulic or pneumatic power. On drilling rigs that do not have a hydraulic power system, motor 41 can be actuated using conventional rig-based air systems. In certain instances, low-pressure air from a rig air system may be directed to a compressor in order to increase the pressure of such air in order to operate motor 41. When a hydraulic rotary actuator is used, the apparatus is relatively compact, thereby conserving valuable space on a rig. Because hydraulic rotary actuators require less hydraulic fluid, smaller volumes of hydraulic fluid are needed to actuate the motor and lift slips from a spider bowl. As such, a manual hand pump can be used in to actuate the powered hand slips of the present invention in event of main power source failure.

In the preferred embodiment, yoke 42 has a spread-width from side to side (denoted by dimension “x” on FIG. 3) that is larger than the diameter of the upper opening to spider bowl 21. Further, yoke 42 has a plurality of mounting eyes 46. In operation, hand slips (not shown in FIG. 3) are aligned with spider bowl 21; yoke 42 is connected to such hand slips via mounting eyes 46 using suitable linkages. Such linkages can include, but are not necessarily limited to, chains or similar devices.

FIG. 4 depicts a side view of powered hand slips 1 of the present invention installed on spider body 20. Mounting bracket 10 is attached to the side of spider body 20. Said spider body 20 has spider bowl 21, and is typically installed at or near the rig floor of a drilling rig.

Collars 30 and 31 having inclined surfaces are mounted to the upper surface of spider body 20. Said collars 30 and 31 define inclined shoulders that are wider at the upper end of said collars (30 a and 31 a) than at the bottom of said collars (30 b and 31 b). Motor 41 (partially obscured from view in FIG. 4) having drive shaft 45 is attached to mounting bracket 10 using mounting plate 44. Lever arm 43 extends from drive shaft 45 of motor 41 to said yoke 42.

FIG. 5 depicts an overhead view of the powered hand slips of the present invention installed on a spider body 20 having a spider bowl 21. Collars 30 and 31 having inclined surfaces are mounted to the upper surface of spider body 20. Said collars 30 and 31 define inclined shoulders that are wider at the upper end of said collars (30 a and 31 a) than at the bottom of said collars (30 b and 31 b), and serve as guides for slips to move in and out of said spider bowl 21.

Motor 41 is affixed to mounting plate 44. In the preferred embodiment, motor 41 is a rotary actuator having horizontal drive shaft 45. Lever arms 43 extend from drive shaft 45 of motor 41 to yoke 42. Motor 41 is mounted to spider body 20 and offset relative to the central axis of spider bowl 21. Yoke 42 has a spread-width from side to side that is larger than the diameter of the upper opening to spider bowl 21. Further, yoke 42 has a plurality of mounting eyes 46 for connection to a set of hand slips via suitable linkage(s).

FIG. 6 depicts a side view of powered hand slips 1 of the present invention installed on spider body 20. Mounting bracket 10 is attached to the side of spider body 20. Said spider body 20 has a central bore defining spider bowl 21, and is typically installed at or near the rig floor of a drilling rig. Pipe section 50 is disposed through the central bore of spider body 20 and is received within said spider bowl 21.

Collars 30 and 31 having inclined surfaces are mounted to the upper surface of spider body 20. Said collars 30 and 31 define inclined shoulders that are wider at the upper end of said collars (30 a and 31 a) than at the bottom of said collars (30 b and 31 b). Motor 41 is affixed to mounting plate 44. In the preferred embodiment, motor 41 is a rotary actuator having horizontal drive shaft 45. Lever arms 43 extend from drive shaft 45 of motor 41 to yoke 42. Motor 41 is mounted to spider body 20, and is offset relative to the central axis of spider bowl 21. Yoke 42 has a spread-width from side to side that is larger than the diameter of the upper opening of spider bowl 21. Further, yoke 42 has a plurality of mounting eyes 46 for connection to a set of hand slips.

Hand slips 60 are generally aligned with said spider bowl 21, and are connected to mounting eyes 46 of yoke 42 using suitable linkages, such as chains 61. In FIG. 6, said hand slips 60 are depicted in an upper, retracted position. Said hand slips 60 are pivotally operable between said upper, retracted position and a lower, gripping position.

Slips 60 are moved between such upper and lower positions via the lifting mechanism of the present invention. Specifically, when motor 41 is actuated, said motor 41 causes said lever arms 43 to pivot about a pivot axis passing through drive shaft 45 of motor 41. In turn, yoke 42 moves in the desired direction. Movement of yoke 42 results in movement of slips 60 in the desired direction. During normal raising or lowering of slips 60, motor 41 acts to retain such slips 60 in the upper or lower position, respectively. The rate of raising or lowering the slips can be controlled by said motor that, in turn, can be controlled from a remote location using a remote control device for said motor 41.

As discussed above, slips 60 are pivotally operable between an upper, retracted position and a lower, gripping position. FIG. 7 depicts slips 60 in a lower, gripping position. In such position, the cooperating inclined surfaces of spider bowl 21 and slips 60 situated therein serve to engage said slips against the exterior surface of pipe section 50 extending through said spider bowl 21. As such, when the weight of pipe section 50 is transferred to slips 60, said slips 60 will move downwardly relative to stationary spider bowl 21. The cooperating inclined surfaces of slips 60 and spider bowl 21 urge said slips to move radially inward to engage against, and grip, pipe section 50.

Use of a rotary actuator as the motor for the present invention is beneficial, because it permits a lower profile for the powered hand slips device of the present invention. A lower profile permits the slips to be set at a lower level, which in turn means that tong operators can work lower (i.e., closer to the rig floor) resulting in a safer working environment.

A custom manifold system prevents such hand slips from falling in the event that power is lost to the system. A secondary “hydraulic fuse” is included in such manifold to allow a load to break mechanical shear pin and permitting such load to come down under it's own power. This in turn limits damage caused when an elevator inadvertently collides with the powered hand slips of the present invention.

As set forth above, manual manipulation of hand slips 60 can be inefficient, difficult and, in many cases, dangerous. When setting hand slips 60, personnel are typically required to grab such hand slips, lift the slips and then insert said slips into spider bowl 21 around the exterior surface of pipe section 21. Alternatively, when removing hand slips 60, personnel are generally required to grab and lift such slips 60 out of spider bowl 21. Because casing spiders are frequently situated at or near the rig floor, such actions often require personnel to bend over and/or lift in awkward positions, thereby increasing the risk of injury to such personnel. The present invention provides an automated means for raising hand slips 60 from spider bowl 21 in order to disengage such slips 60 from gripping pipe section 50 and, alternatively, lowering said slips into said slip bowl 21 in order to engage such slips 60 against pipe section 50. The present invention is easily integrated with existing rig equipment, and facilitates easy and efficient handling of tubular goods on a drilling rig, such as casing, drill pipe and/or the like.

Although the present invention has been depicted in a particular form constituting a preferred embodiment, it will be understood that various changes and modifications in the illustrated and described structure can be effected without departure from the basic principles which underlie the invention. Changes and innovations of this type are deemed to be circumscribed by the spirit and scope of the invention except as such spirit and scope may be necessarily limited by the appended claims, or reasonable equivalents thereof. 

1. An apparatus for raising and lowering hand slips comprising: a. a motor having a horizontal drive shaft; b. a yoke connected to said drive shaft; c. means for affixing said motor to a spider bowl; and d. a linkage for connecting said yoke to said hand slips.
 2. The apparatus of claim 1, wherein said motor is actuated using hydraulic power.
 3. The apparatus of claim 2, wherein said motor is actuated using pneumatic power.
 4. The apparatus of claim 1, wherein said means for connecting said yoke to said hand slips comprises a chain.
 5. The apparatus of claim 1, wherein said motor is a rotary actuator. 